In the Phase II continuation project, we propose to extend development of the Neuroskill(tm) into commercially viable, robust market product that will be submitted to the FDA for regulatory clearance and then introduced to the market. Neuroskill(tm) is a device for assessment and monitoring of fine motor control in patients with neurological disorders, such as Parkinson's disease and stroke. In Phase II, the prototype of the device was designed, built and successfully tested on Parkinson's patients in the pilot experimental studies on measuring the effects of the levodopa treatment on motor fluctuations, and on detecting of the ipsilateral motor control impairment in patients with hemispheric stroke and subsequent monitoring of their improvement during rehabilitation. The device consists of an instrumented pen with imbedded two-axis micro-accelerometer and pressure sensor, electronics interface unit for digitizing input data for computer analysis, and a special software package for analysis of handwriting micro-dynamics. Specifically, during the continuing Phase II effort, we plan to include a wireless communication interface between the pen and a computer, develop an alternative configuration with the digitized graphical pad as a medium for capturing handwriting dynamic information, include a voice communication option for navigating the tests, and ensure the device meets medical equipment quality standards at minimal cost. Software upgrades will improve user friendliness, integrate new algorithms to optimize the code, modify the software to include additional utility features, such as effective graphical interface for rapid clinical review, and will port the research code into an FDA- approvable code base. An extended experimental study with Parkinson's disease patients on effect of the levodopa medication on motor fluctuations will be conducted to demonstrate sensitivity and efficacy of the device. All necessary steps to prepare application for 510(k) clearance will be completed. There is a compelling need to develop quick, objective and sensitive tests of motor fluctuations in Parkinson's disease, and the proposed device addresses this necessity and can become a valuable clinical marker in PD. The current project will result in an FDA-cleared product that can be widely used to increase the accuracy of early of Parkinson's disease diagnosis, monitoring acute and long-term effects of therapeutic treatment and optimization of the post-operative DBS adjustment procedures. The proposed device will bring both health care benefits and cost reduction associated with treatment of Parkinson's disease and related disorders. It will provide the clinician an easy tool for monitoring the patients and will help in designing the best regimen of medications in order to achieve the maximal improvement in the patient's condition while alleviating the severe motor fluctuations as a side effect of the treatment. The device option of remote monitoring the patients in the convenience of their home or workplace will also create more comfort for the patient, as well as let them avoid extra travel to the doctor's office.